Russia’s election authorities on Wednesday, January 25 officially registered tycoon Mikhail Prokhorov to run in the presidential elections in March, RIA Novosti reported.

The billionaire has now become one of five campaign hopefuls. The four other registered candidates are Prime Minister Vladimir Putin, moderate social democratic leader Sergei Mironov, populist firebrand Vladimir Zhirinovsky and communist leader Gennady Zyuganov.

The signatures collected by Prokhorov satisfy all requirements, the Central Election Committee (CEC) said. The checking of signature sheets in support of Prokhorov revealed 4.38 percent were invalid, which is under the legal 5 percent threshold.

Yabloko party founder Grigory Yavlinsky has been disqualified from the race over invalid support signatures, the CEC said on Tuesday.

Yavlinsky collected two million signatures in support of his bid as required by law but two consecutive checks, the second of which was wrapped up Tuesday evening, showed 25.66 percent of them to be invalid, Commission Secretary Nikolai Konkin said. The law caps the amount of invalid signatures at five percent.